1. Field of the Invention
The present general inventive concept relates to an ink jet head and, more particularly, to a filter plate usable with an ink jet head, an ink jet head with the filter plate, and a method of fabricating the filter plate.
2. Description of the Related Art
An ink jet recording device is a device for printing an image by ejecting fine droplets of ink to desired positions on a recording medium. The ink jet recording device has been widely used since it is inexpensive and is capable of printing numerous colors at a high resolution. The ink jet recording device includes an ink jet head for ejecting the ink and an ink container for storing the ink to be supplied to the ink jet head. The ink jet head includes a substrate having a chip shape, and a flow path structure disposed on the substrate to define a shape of an ink flow path including an ink chamber and a nozzle. In addition, the ink chamber is connected to the ink container by a common feedhole extending through the substrate.
One of the problems that affects the ink jet head is clogging of the ink flow path due to particles. The particles may be introduced into the ink flow path during a manufacturing process of the ink jet head or the particles may be contained in the ink. When the particles have a dimension larger than that of the ink flow path, the ink flow path is blocked by the particles, thereby deteriorating quality of a print image, and in some cases, preventing the ink jet head from ejecting the ink. In an attempt to solve the problem described above, a stainless steel mesh filter has been adapted to a conventional ink container to prevent the particles from being introduced into the ink flow path from the ink container. However, in order to obtain a high resolution print image, ink droplet sizes have been reduced by reducing the size of the ink flow path. As a result of this reduction in size of the ink flow path, it has become difficult to use the mesh filter due to a limitation of cost and process.
A method of forming filtering members on an ink jet head substrate during a manufacturing process of the ink jet head has also been developed. Examples of the ink jet head including the filtering members are disclosed in U.S. Pat. Nos. 5,463,413 and 6,626,522. The ink jet heads disclosed in U.S. Pat. Nos. 5,463,413 and 6,626,522 include a chamber layer disposed on a substrate to define an ink chamber and having a three-sided barrier structure. The filtering members are provided in an island shape between a common feedhole extending through a center portion of the substrate and the chamber layer. The filtering members are formed on the same plane of the substrate in the same process as the chamber layer. However, according to U.S. Pat. Nos. 5,463,413 and 6,626,522, it may be difficult to filter the particles having a high aspect ratio. In addition, since the filtering members are formed on the same plane of the substrate as the chamber layer, it may be difficult to fabricate the ink jet head with high density. Furthermore, using the filtering members disclosed in the U.S. Pat. Nos. 5,463,413 and 6,626,522, it may be impossible to adapt the ink jet head to have a structure in which the ink that is supplied from the ink container is introduced through a bottom surface of the ink chamber.